feat:centralise temp-file management & cleanup across app/docker (#3797)

# Description of Changes
Introduces TempFileManager, registry, and scheduled cleanup service;
aligns all Docker images and runtime scripts to use a dedicated
/tmp/stirling-pdf directory; updates controllers, utilities, and tests
to use the new API; adds configurable system.tempFileManagement section.

Closes #(issue_number)

---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing)
for more details.

---------

Co-authored-by: a <a>

testing/test.sh

@@ -55,10 +55,12 @@ capture_file_list() {
         -not -path '/config/*' \
         -not -path '/logs/*' \
         -not -path '*/home/stirlingpdfuser/.config/libreoffice/*' \
-        -not -path '*/tmp/PDFBox*' \
+        -not -path '*/home/stirlingpdfuser/.pdfbox.cache' \
+        -not -path '*/tmp/stirling-pdf/PDFBox*' \
+        -not -path '*/tmp/stirling-pdf/hsperfdata_stirlingpdfuser/*' \
         -not -path '*/tmp/hsperfdata_stirlingpdfuser/*' \
-        -not -path '*/tmp/lu*' \
-        -not -path '*/tmp/tmp*' \
+        -not -path '*/tmp/stirling-pdf/lu*' \
+        -not -path '*/tmp/stirling-pdf/tmp*' \
         2>/dev/null | xargs -I{} sh -c 'stat -c \"%n %s %Y\" \"{}\" 2>/dev/null || true' | sort" > "$output_file"
 
     # Check if the output file has content
@@ -74,8 +76,10 @@ capture_file_list() {
             -not -path '/config/*' \
             -not -path '/logs/*' \
             -not -path '*/home/stirlingpdfuser/.config/libreoffice/*' \
+            -not -path '*/home/stirlingpdfuser/.pdfbox.cache' \
             -not -path '*/tmp/PDFBox*' \
             -not -path '*/tmp/hsperfdata_stirlingpdfuser/*' \
+            -not -path '*/tmp/stirling-pdf/hsperfdata_stirlingpdfuser/*' \
             -not -path '*/tmp/lu*' \
             -not -path '*/tmp/tmp*' \
             2>/dev/null | sort" > "$output_file"